⭐ Milk + Lemon Juice (Best Nut-Free Option)
1 cup milk + 1 tablespoon lemon juice (let sit 5 minutes before use)Milk combined with lemon juice mimics the acidity of buttermilk by slightly curdling the milk, which helps tenderize gluten and activate baking soda or yeast in focaccia dough. This acidity is crucial for achieving the characteristic soft crumb and slight tang in focaccia.
For best results, use whole milk for moisture and richness, and allow the mixture to sit for at least 5 minutes to develop acidity before adding to the dough. Avoid using skim milk as it may reduce tenderness.
Compared to buttermilk, this substitute produces a focaccia with very similar texture and flavor, preserving the light, airy crumb and subtle tanginess expected in traditional recipes.